A multi-phase switch is typically mounted in an enclosure and includes a line terminal and a load terminal for each phase of a multi-phase circuit The switch usually has a base and an operating mechanism with pivotable blades which pass through arc chambers until they engage a stationary contact. In this position, the current freely passes through the switch. A lever may be moved back and forth to raise or lower the knife blades, thus disconnecting or connecting the circuit.
One type of known fusible switch assembly for a multiphase circuit includes an insulating line base, a plurality of terminals, multiple knife blades which are connected to one set of terminals, and contacts connected to another set of terminals. The knife blades can be rotated against the contacts, so that current flows through the switch, by a rotor mechanism. Included with the switch assembly is a load base assembly which connects with the line base through respective fuses.
Other types of switches externally mount the operating mechanism to one or two opposing side portions of the base with fasteners, which require additional assembly and alignment operations during manufacture.
Yet other types of switches mount the operating mechanism to the external enclosure rather than to the switch base, as exemplified by U.S. Pat. No. 3,684,849.
A problem with any of the above-described switches is the difficulty involved in mounting or replacing them. The operating mechanism often must be separately mounted to the base and the base mounted to the outer enclosure. There remains a need for a switching assembly where the switch base and operating mechanism are fitted together and easily mounted simultaneously.